mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-28 20:53:54 +02:00
90 lines
2.7 KiB
C
90 lines
2.7 KiB
C
/*
|
|
* LOAS AudioSyncStream demuxer
|
|
* Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at>
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include "libavutil/intreadwrite.h"
|
|
#include "libavutil/internal.h"
|
|
#include "avformat.h"
|
|
#include "internal.h"
|
|
#include "rawdec.h"
|
|
|
|
static int loas_probe(AVProbeData *p)
|
|
{
|
|
int max_frames = 0, first_frames = 0;
|
|
int fsize, frames;
|
|
uint8_t *buf0 = p->buf;
|
|
uint8_t *buf2;
|
|
uint8_t *buf;
|
|
uint8_t *end = buf0 + p->buf_size - 3;
|
|
buf = buf0;
|
|
|
|
for(; buf < end; buf= buf2+1) {
|
|
buf2 = buf;
|
|
|
|
for(frames = 0; buf2 < end; frames++) {
|
|
uint32_t header = AV_RB24(buf2);
|
|
if((header >> 13) != 0x2B7)
|
|
break;
|
|
fsize = (header & 0x1FFF) + 3;
|
|
if(fsize < 7)
|
|
break;
|
|
fsize = FFMIN(fsize, end - buf2);
|
|
buf2 += fsize;
|
|
}
|
|
max_frames = FFMAX(max_frames, frames);
|
|
if(buf == buf0)
|
|
first_frames= frames;
|
|
}
|
|
if (first_frames>=3) return AVPROBE_SCORE_MAX/2+1;
|
|
else if(max_frames>100)return AVPROBE_SCORE_MAX/2;
|
|
else if(max_frames>=3) return AVPROBE_SCORE_MAX/4;
|
|
else if(max_frames>=1) return 1;
|
|
else return 0;
|
|
}
|
|
|
|
static int loas_read_header(AVFormatContext *s,
|
|
AVFormatParameters *ap)
|
|
{
|
|
AVStream *st;
|
|
|
|
st = avformat_new_stream(s, NULL);
|
|
if (!st)
|
|
return AVERROR(ENOMEM);
|
|
|
|
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
|
|
st->codec->codec_id = s->iformat->value;
|
|
st->need_parsing = AVSTREAM_PARSE_FULL;
|
|
|
|
//LCM of all possible AAC sample rates
|
|
avpriv_set_pts_info(st, 64, 1, 28224000);
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVInputFormat ff_loas_demuxer = {
|
|
.name = "loas",
|
|
.long_name = NULL_IF_CONFIG_SMALL("LOAS AudioSyncStream"),
|
|
.read_probe = loas_probe,
|
|
.read_header = loas_read_header,
|
|
.read_packet = ff_raw_read_partial_packet,
|
|
.flags= AVFMT_GENERIC_INDEX,
|
|
.value = CODEC_ID_AAC_LATM,
|
|
};
|